Barback transforms now pass through the primary input by default.

pkg/barback/test/package_graph/lazy_transformer_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library barback.test.package_graph.lazy_asset_test;
 
 import 'package:barback/barback.dart';
 import 'package:barback/src/utils.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../utils.dart';
 
 main() {
   initConfig();
   test("requesting a lazy asset should cause it to be generated", () {
     initGraph(["app|foo.blub"], {"app": [
       [new LazyRewriteTransformer("blub", "blab")]
     ]});
     updateSources(["app|foo.blub"]);
     expectAsset("app|foo.blab", "foo.blab");
     buildShouldSucceed();
   });
 
   test("calling getAllAssets should cause a lazy asset to be generated", () {
     var transformer = new LazyRewriteTransformer("blub", "blab");
     initGraph(["app|foo.blub"], {"app": [[transformer]]});
     updateSources(["app|foo.blub"]);
-    expectAllAssets(["app|foo.blab"]);
+    expectAllAssets(["app|foo.blub", "app|foo.blab"]);
     buildShouldSucceed();
     expect(transformer.numRuns, completion(equals(1)));
   });
 
   test("requesting a lazy asset multiple times should only cause it to be "
       "generated once", () {
     var transformer = new LazyRewriteTransformer("blub", "blab");
     initGraph(["app|foo.blub"], {"app": [[transformer]]});
     updateSources(["app|foo.blub"]);
     expectAsset("app|foo.blab", "foo.blab");
@@ skipping 130 matching lines @@
       "it from being materialized", () {
     var transformer = new LazyBadTransformer("app|foo.out");
     initGraph(["app|foo.txt"], {"app": [[transformer]]});
 
     updateSources(["app|foo.txt"]);
     expectNoAsset("app|foo.out");
     buildShouldFail([isTransformerException(equals(LazyBadTransformer.ERROR))]);
     expect(transformer.numRuns, completion(equals(0)));
   });
 }